Sapphire lens is being increasingly applied to various wearable products, attributing to its superior scratch-resistance performance. However, there are many bottlenecks in the processing of sapphire lens, including long processing cycle, multiple production processes, and excessively high cost, which restrict the application of sapphire lens in mobile phones and other electronic products in a large scale.
In the processing of conventional sapphire lenses, in order to fulfill the appearance requirements and usage requirements of the lenses, multiple additional processes are required following sapphire sheet molding and double-side fine polishing. These additional processes include for example, electroplating on one side of the sapphire sheet an anti-fingerprint film, and screening printing on the other side a frame shading, curing, functional ink screen printing, further curing, electroplating a coating film, and so on. The structure of the sapphire product thus prepared includes, in the thickness direction, an anti-fingerprint film layer 2, a sapphire sheet 1, a frame ink layer 5, a functional ink layer 6 and a coating film layer 7.
For example, patent application CN201410294265.7 discloses a processing method for a mobile phone panel of a sapphire material, with the following processes: material—cutting—chamfering—coarse grinding—annealing—DMP—CMP—cleaning—film coating—screen printing—finished product inspection. These processes are: i. cutting: cutting the crystal block into plate materials for subsequent processing; ii. chamfering: trimming the edges of the crystal plate into an arc shape, improving the mechanical strength of the edge of the plate, and avoiding defects caused by strain concentration; iii. coarse grinding: removing crystal plate cutting damage layer caused by crystal plate cutting and improving the flatness of the crystal plate: iv. annealing: improving the excessively great strain concentration BOW due to mechanical processing; v. DMP: improving the damage layer caused by coarse grinding and improving the surface roughness of the crystal plate: vi. CMP: improving the roughness of the crystal plate to achieve nanometer-level fineness: vii. film coating: performing anti-fingerprint film coating on the crystal plate; viii. screen printing: screen printing on one side of the crystal plate to increase light absorption. The above method can obtain a sapphire mobile phone panel that does not have damage layer on the surface and of which a roughness reaches nanometer level. Meanwhile, the above method greatly shortens the producing period, which saves production cost and increases labor productivity.
However, the multiple processes mentioned above performed on sapphire sheet still cost a rather long processing period, a low yield and thereby causing high cost for producing sapphire lens. Therefore, it is a major problem for introducing sapphire lenses into the market to reduce the complexity of the process, improve the processing efficiency and thereby reducing the production cost of the sapphire lenses.
In other words, the processing time of each sapphire lens is rather high caused by the steps of screen printing, curing and electroplating performed on the sapphire sheet, which severely limits the production capacity of sapphire lens. Therefore, there is a need in this field for a sapphire lens having a new structure instead of the sapphire lens produced by the above method to solve the problem of insufficient production capacity in sapphire lens production.